Suppose on pushing a button an object is to be notified, but it is not known until runtime which object should be notified. Which of the following programming constructs should be used to implement this idea?

1. Delegates are not type-safe.
2. Delegate is a user-defined type.
3. Only one method can be bound with one delegate object.
4. Delegates can be used to implement callback notification.
5. Delegates permit execution of a method on a secondary thread in an asynchronous manner.

class Sample
{
    public int MyFun(int i)
    {
        Console.WriteLine("Welcome to CuriousTab.com !" );
        return 0;
    }
}

delegate void del(int i);
Sample s = new Sample();
deld = new del(ref s.MyFun);
d(10);

delegate int del(int i);
Sample s = new Sample(.);
del = new delegate(ref MyFun);
del(10);

Sample s = new Sample();
delegate void del = new delegate(ref MyFun);
del(10);

delegate int del(int i);
del d;
Sample s = new Sample();
d = new del(ref s.MyFun);
d(10);

class Sample
{
    public int func(int i, Single j)
    {
        /* Add code here. */
    }
}

1. Static data
2. Instance data
3. Static function/subroutine
4. Instance function/subroutine

1. Inheritance is a prerequisite for using delegates.
2. Delegates are type-safe.
3. Delegates provide wrappers for function pointers.
4. The declaration of a delegate must match the signature of the method that we intend to call using it.
5. Functions called using delegates are always late-bound.

1. Stack
2. Tree
3. SortedDictionary
4. SortedArray

public class TestCuriousTab
{
    public void TestSub<M> (M arg)
    {
        Console.Write(arg);
    }
}
class MyProgram
{
    static void Main(string[] args)
    {
        TestCuriousTab tab = new TestCuriousTab();
        tab.TestSub("CuriousTab ");
        tab.TestSub(4.2f);
    }
}